
Well no, more like its toxic and we know it, but it doesn't actually bother anyone. I sort of relate it to the fact that my friends and I just call each other "bitches" while in the moment, but nobody actually takes it to heart because we've known each other for years and things like that don't faze us, and we don't consider it a true insult, which for example, would instead be something like an attack based on a personal issue/circumstance.
Also, in that moment it felt more like the short haired friend was more annoyed in her friend's stead because she was being viewed inappropriately. Since it seems like she wasn't that in love w/ her boyfriend, and she even started to question the reason she got upset.
It's so hard to explain so I'm done here, or maybe it's just how my friendships are but that's because we've known each other for years, so maybe my views on true friendship is different, where people aren't sensitive and small things like that, we don't care...
Well, this is just my input and take of the situation

The reason why the other girl asked her Bf to praise her friend wasn’t for a good reason lmao. Like that girl just asked her Bc to say it so she can just break up with him and/or get irritated lol, the more he said, the more reasons she had to break it off.
And I think you’re taking the “slut” comment too seriously. like the two of them are close enough to use offensive language in a casual, non offensive way. Plus u also have to consider this is a translated comic; the Japanese word may have mean something less harsh.
The blonde doesn’t seem to be as bonded as the other, considering she was bashing her to her ex calling her a slut while the other wanted her bf to praise her. I understand it’s a inferiority complex but don’t treat your friend like that because of it.